Floribunda rose plant named ‘GRAdkpk’

ABSTRACT

‘GRAdkpk’ is a new and distinct floribunda type  Rosa  hybrid cultivar which is characterized by the combination of an upright to semi-weeping growth habit, excellent resistance to  Diplocarpon rosae , nearly continuous flowering, lavender pink double-type flowers which fade to mauve pink, a strong rose fragrance, and the stability of these characteristics from generation to generation. The new cultivar is generally suited to landscape applications.

Latin name of genus and species: The Latin name of the genus and speciesof the novel variety disclosed herein is Rosa hybrid.

Variety denomination: The inventive variety of Rosa hybrid disclosedherein has been given the variety denomination ‘GRAdkpk’.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to the Australian Plant Breeder'sRights application number 2015/088, filed on Apr. 27, 2015, which isherein incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct Rosa hybrid,floribunda rose cultivar, which has been given the variety denominationof ‘GRAdkpk’.

Parentage: ‘GRAdkpk’ is a seedling selection which resulted from thecontrolled cross-pollination of an unnamed Rosa hybrid female breedingline and an unnamed Rosa hybrid male breeding line. Both parents,developed by the same inventor and never commercially released,exhibited traits deemed commercially significant and desirable.

After many years of trialing, the female parent was confirmed to possessa combination of desirable traits such as complete resistance to roseblack spot disease, complete resistance to powdery mildew, and flowerswith a strong citrus-like perfume borne on a bushy plant growing to 1.2m tall and wide. The male parent was selected for use in breeding aftertrialing confirmed the presence of strong true-rose perfume and abright, modern flower color. During the summer of 2010, the femaleparent was emasculated and was manually pollinated with pollen from themale parent. In autumn of 2010, seed was collected from hips produced bythe female parent and a number of seedlings were grown to a mature size,including the claimed plant. These progeny were further evaluated fordesirable traits such as black spot disease resistance and strongperfume, and in June of 2011 the claimed plant was first observed. InJanuary of 2013, after further evaluation for desirable traits, theclaimed plant was deemed to be garden-worthy and suited to widespreadcultivation. It was given the denomination, ‘GRAdkpk’.

Asexual Reproduction: Asexual propagation of ‘GRAdkpk’, by way ofsoftwood stem cuttings, was first performed in May of 2011 at theinventor's nursery in Highfields, Australia. Through more than twelvesubsequent generations, the unique features of this cultivar have provento be stable and true to type.

SUMMARY OF THE INVENTION

The following characteristics have been repeatedly observed andrepresent the distinguishing characteristics of the new Rosa cultivar‘GRAdkpk’. These traits, in combination, distinguish ‘GRAdkpk’ as a newand distinct cultivar.

-   -   1. Rosa hybrid ‘GRAdkpk’ exhibits an upright to semi-weeping        growth habit; and    -   2. Rosa hybrid ‘GRAdkpk’ exhibits excellent resistance to the        plant pathogen, Diplocarpon rosae, commonly referred to as rose        black spot disease; and    -   3. Rosa hybrid ‘GRAdkpk’ exhibits nearly continuous flowering;        and    -   4. Rosa hybrid ‘GRAdkpk’ exhibits a double flower type; and    -   5. Rosa hybrid ‘GRAdkpk’ exhibits lavender pink flowers which        fade to mauve pink; and    -   6. Rosa hybrid ‘GRAdkpk’ exhibits flowers with a strong rose        fragrance.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 illustrates, as nearly true as it is reasonably possible to makethe same in color photographs of this type, an exemplary 15 month old‘GRAdkpk’ plant grown outdoors at the inventor's commercial nursery inHighfields, Australia.

FIG. 2 illustrates, as nearly true as it is reasonably possible to makethe same in color photographs of this type, the typical foliage andflower of ‘GRAdkpk’.

DETAILED BOTANICAL DESCRIPTION

The following observations and measurements, made in February of 2016,describe averages of two own-root specimens of one year old ‘GRAdkpk’plants. The plants were grown outdoors in 20 cm containers, in asoilless pine bark based growing media, at the inventor's nursery inHighfields, Australia. No shade or supplemental light was provided.Temperatures ranged from approximately 17 to 35 degrees Celsius duringthe day and 7 to 18 degrees Celsius at night. Standard practices forirrigation, fertilizer and pest control were applied at appropriatetimes during the growing season. The plants were pruned three timesduring the growing season using accepted techniques for rose pruning.

Those skilled in the art will appreciate that certain characteristicswill vary with older or, conversely, with younger plants. ‘GRAdkpk’ hasnot been observed under all possible environmental conditions. Wheredimensions, sizes, colors and other characteristics are given, it is tobe understood that such characteristics are approximations or averagesset forth as accurately as practicable. The phenotype of the variety maydiffer from the descriptions set forth herein with variations inenvironmental, climatic and cultural conditions. Color notations arebased on The Royal Horticultural Society Colour Chart, The RoyalHorticultural Society, London, 2007 Fifth Edition except where commonterms of color are used.

A botanical description of ‘GRAdkpk’ and comparisons with the parentsand the most similar commercial cultivar of Rosa hybrid are providedbelow.

-   General plant description:    -   -   Growth habit.—Upright to semi-weeping.        -   Growth rate.—Approximately 1 year to reach 40 cm.        -   Dimensions.—40 cm tall and 40 cm wide.        -   Environmental tolerance.—Very good heat tolerance; cold            hardiness is unknown.        -   Disease resistance.—Excellent resistance to powdery mildew            (Sphaerotheca pannosa) and blackspot (Diplocarpon rosae).        -   Propagation.—Technique — Softwood stem cuttings. Time to            initiate roots — About 13 days at approximately 21 degrees            Celsius at root zone and 18 degrees Celsius ambient            temperature. Time to produce a rooted cutting — About 25            days at approximately 21 degrees Celsius at root zone and 18            degrees Celsius ambient temperature.-   Root system: White fibrous roots with many root hairs extending from    lesser roots in a featherlike arrangement.-   Branches:    -   -   Branching habit.—Irregular branching from mature branches,            breaking first from the uppermost buds near the apex of each            shoot.        -   Quantity.—Numerous.        -   General dimensions.—Approximately 15 cm long; 0.7 cm in            diameter near the base and tapering to 0.5 cm.        -   Immature branches.—Diameter — Approximately 0.4 cm. Texture            and pubescence — Smooth with prickles; moderately to heavily            pubescent. Color — Near RHS 142B. Prickles — Density —            Moderate. Color — Near RHS 165C. Shape — Concave. Texture —            Smooth.        -   Mature branches.—Diameter — Approximately 0.7 cm, after one            year. Texture and pubescence — Smooth with prickles;            glabrous. Color — Near RHS 143B. Prickles — Density —            Moderate. Color — Near RHS 144C. Shape — Concave. Texture —            Smooth.-   Leaves:    -   -   Arrangement.—Alternate imparipinnate compound leaves.        -   Quantity.—Approximately 6 per mature branch.        -   Attachment.—Petiolate.        -   Leaf internode length.—2.2 cm.        -   Dimensions.—Approximately 8 cm long and 6 cm wide.        -   Petiole.—Dimensions — Average of 1.0 to 2.0 cm long and 0.1            to 0.2 cm wide. Color — Near RHS 142C. Texture and            pubescence — Rough and glabrous. Prickles — Small blunt            prickle is present. Stipitate glands — Not present.        -   Stipule.—Dimensions — 1.0 cm long and 0.4 cm wide. Color —            Near RHS 142C. Texture and pubescence — Smooth and glabrous.            Margins — Ciliate. Apex — Acuminate. Base — Winged. Prickles            — Not present. Stipitate glands — Not present.        -   Rachis.—Dimensions — 1.5 cm long and 0.2 cm wide. Color —            Near RHS N138C. Prickles — Present. Stipitate glands — Not            present.        -   Leaflets.—Quantity — Five leaflets on axillary leaves.            Dimensions — Average size of the terminal leaflet is 3.5 cm            long and 3.0 cm wide. Shape — Ovate. Apex — Acuminate. Base            — Ovate. Margins — Serrated. Texture, pubescence and luster,            adaxial surface — Smooth, glabrous, and semi-glossy.            Texture, pubescence and luster, abaxial surface — Rough,            glabrous, and matte. Juvenile foliage color, adaxial surface            — Near RHS 143A, with anthocyanin intonations, near RHS 53A,            at the margins and midrib. Juvenile foliage color, abaxial            surface — Near RHS 139C, with anthocyanin intonations, RHS            53A. Mature foliage color, adaxial surface — Near RHS N138B.            Mature foliage color, abaxial surface — Near RHS 139C.            Venation — Pinnate. Venation color, adaxial surface — Near            RHS N138B. Venation color, abaxial surface — Near RHS 139D.            Petiolule — Dimensions — 0.3 cm long and 0.1 cm wide. Color            — Near RHS 144D. Prickles — Not present. Texture — Smooth.-   Inflorescence:    -   -   Inflorescence type.—Terminal corymb consisting of            approximately 2 to 6 pedicellate flowers.        -   Blooming habit.—Almost continuous from October through June            in the southern hemisphere.        -   Time to flower.—6 to 8 weeks for a new stem to mature and            flowering begins to occur once a stem matures.        -   Dimensions.—17 cm from the base of the lowest pedicel to the            farthest distal flower and the width from farthest            outstretched flower on one side of the inflorescence to the            farthest outstretched flower on the opposite side is 22 cm.        -   Peduncle.—Dimensions — 4.5 cm long and 0.2 cm in diameter.            Color — Near RHS 144A. Strength — Strong. Texture and            pubescence — Rough and glabrous. Prickles — Not present.-   Bud:    -   -   Shape.—Ovate.        -   Size.—2.0 cm long and 1.5 cm in diameter.        -   Color.—Near RHS 137D.-   Flower:    -   -   Pedicel.—Dimensions — 5 cm long. Color — Near RHS 144A.            Strength — Strong. Texture — Rough.        -   Calyx.—General — Comprised of five polysepalous sepals, with            strong foliaceous appendages present on all sepals. Diameter            of calyx — 0.4 cm. Sepals — Color, interior surface — RHS            130D. Color, exterior surface — RHS 137D. Dimensions — 2.0            cm long and 0.6 cm wide. Apex — Acuminate. Base — Flat at            union with receptacle. Quantity — Five. Pubescence — Densely            puberulent. Margins — Two to three strong foliaceous            appendages. Stipitate glands — Not present.        -   Corolla.—General shape of corolla — Cupped and well-rounded            at anthesis; aging to a loose whorl. Rate of opening — 6            days from bud to anthesis. Dimensions — Approximately 8 cm            in diameter and 5 cm deep. Fragrance — Strong rose scent.            Lastingness — On the plant for 5 days after anthesis.            Persistence — Self-cleaning.        -   Petals.—Petal count — Exhibits double flowers with            approximately 36 petals under normal conditions. Petal            arrangement — Irregularly rounded whorl, with loose outer            whorl. Dimensions — 3.2 cm long and 2.2 cm wide. Petal shape            — Obovate. Apex — Rounded to cordate. Base — Flattened, then            obtuse. Petal reflex — Slightly reflexed at apex. Petal            margin — Entire; slightly undulating. Texture — Soft. Aspect            — Slightly ruffled. Petal color, upon opening — Upper            surface — Near RHS 67B. Lower surface — Near RHS N57C. Petal            color, at anthesis — Upper surface — Near RHS 73A. Lower            surface — Near RHS 73B. Fading — Near RHS 52C.-   Reproductive organs:    -   -   Stamens.—Quantity — Approximately 30. Anthers — Shape —            Narrow ovate. Length — 0.1 cm. Color — Near RHS 21B. Pollen            — Many. Pollen Color — Near RHS 3A. Filaments — Color — Near            RHS 8D. Length — Approximately 0.7 cm.        -   Pistils.—Quantity — Approximately 50. Length — Approximately            0.8 cm. Stigma — Shape — Ovate. Color — Near RHS 11B. Style            — Length — Approximately 0.3 cm long. Color — Near RHS 18D.        -   Ovary.—Dimensions — 0.5 cm long and 0.3 cm wide. Color —            Near RHS 3D.        -   Receptacle.—Shape — Pitcher-shaped. Dimensions — 0.5 cm high            and 0.5 cm wide. Color — Near RHS 137D.-   Hip and seed:    -   -   Hip.—Shape — Rounded. Dimensions — 1.5 cm long and 1.7 cm            wide. Texture — Smooth. Color — Near RHS 138B.        -   Seed.—Not present.

COMPARISONS WITH THE PARENTS

The new rose plant ‘GRAdkpk’ may be distinguished from its seed parent,an unnamed breeding line, by the following combination ofcharacteristics:

-   -   1. The flowers of ‘GRAdkpk’ exhibit a distinct lavender pink        general tonality with a rounded form and center petals remaining        erect and cupped for some period of time after anthesis, whereas        the flowers of the seed parent exhibit a soft pink general        tonality and loose, open flowers.    -   2. ‘GRAdkpk’ exhibits an upright to semi-weeping growth habit,        whereas the seed parent exhibits an upright growth habit.

The new rose plant ‘GRAdkpk’ may be distinguished from its pollenparent, an unnamed breeding line, by the following combination ofcharacteristics:

-   -   1. The flowers of ‘GRAdkpk’ exhibit a distinct lavender pink        general tonality with a rounded form and center petals remaining        erect and cupped for some period of time after anthesis, whereas        the flowers of the pollen parent exhibit a purple general        tonality.    -   2. ‘GRAdkpk’ exhibits an upright to semi-weeping growth habit,        whereas the pollen parent exhibits an upright growth habit.    -   3. ‘GRAdkpk’ exhibits juvenile foliage colored near RHS 143A        with anthocyanin intonations, whereas the pollen parent exhibits        juvenile foliage colored near RHS 137C with no anthocyanin        intonations.

COMPARISONS WITH THE MOST SIMILAR VARIETY OF COMMON KNOWLEDGE

Plants of the new cultivar ‘GRAdkpk’ may be distinguished from thecommercial variety Rosa hybrid ‘GRAppl’ (U.S. Plant Pat. No. 26,364) bythe following combination of characteristics:

-   -   1. The flowers of ‘GRAdkpk’ exhibit a distinct lavender pink        general tonality, whereas the flowers of ‘GRAppl’ exhibit a        purple general tonality.    -   2. ‘GRAdkpk’ exhibits a petal count of approximately 36 petals,        whereas ‘GRAppl’ typically possesses 22 petals.    -   3. ‘GRAdkpk’ exhibits average leaf dimensions of 8.0 cm long and        6.0 cm wide, whereas ‘GRAppl’ exhibits average leaf dimensions        of 13.5 cm long and 8.5 cm wide.    -   4. Mature field-grown ‘GRAdkpk’ plants exhibit an average plant        height of 100 cm, whereas ‘GRAppl’ exhibits an average plant        height of 120 cm.    -   5. ‘GRAdkpk’ exhibits a rotund plant shape with more twiggy        stems, whereas ‘GRAppl’ exhibits an upright shape with strong        main stems.

That which is claimed:
 1. A new and distinct variety of Rosa hybridplant named ‘GRAdkpk’, as described and illustrated herein.